The invention relates to optical materials and devices. More particularly, the invention relates to optical materials and devices in which interfacial mixing of electronic states occurs. Even more particularly, the invention relates to nano-wires comprising such optical materials.
Optoelectronic devices such as solar cells, radiation detectors, and light emitting diodes, generally depend upon bulk effects of semiconducting materials. Under such conditions, a single band-gap is accessible, and the overall efficiency of such devices is thereby limited to an upper value. In other applications, such as radiation detectors or light emitting diodes, the band-gap determines the energy of either emission or detection. Solar cells having a single band-gap, for example, are limited to an efficiency of less than about 41 percent.
The concept of increasing efficiency using intermediate band-gap materials has been proposed. Approaches to obtaining such materials include providing an intermediate band by incorporating quantum dots inside a host material.
Intermediate band-gaps are inaccessible in the bulk state. Attempts to fabricate devices utilizing intermediate band-gap materials require complex material assembly techniques and have to date been generally unsuccessful. Therefore, what is needed is an optoelectronic device comprising an intermediate band-gap material.